also the bird of silent flight. if i were to fly him one inch over your head, you'd never hear anything. a parrot or goose -- >> completely silent? >> one last thing, they call tt wise old owl, not because they have a big brain. they have senses, hearing, eyesight, not on the side -- over here like a soup bowl, like this. echo location, he can hunt in total, total darkness. a lot of people don't get to see this owl. >> dangerous in their own way. >> they can be, yes. also so good with rodents, barn owl, for example, can take out 30 mice in an hour. very important that way. protected species, the owl. >> let's take a break, when we come back, the fastest animal on the planet. first, here's one of jack's top five close animal encounters. >> whole cave was alive. okay, if you look up now, look up there. that's all the bird nests. >> those are bats up there. >> bats and birds both. >> okay, let's keep moving.